package com.itheima.reggie.service.impl;

import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.itheima.reggie.common.CustomException;
import com.itheima.reggie.dto.SetmealDto;
import com.itheima.reggie.entity.Dish;
import com.itheima.reggie.entity.Setmeal;
import com.itheima.reggie.entity.SetmealDish;
import com.itheima.reggie.mapper.SetmealMapper;
import com.itheima.reggie.service.DishService;
import com.itheima.reggie.service.SetmealDishService;
import com.itheima.reggie.service.SetmealService;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import java.util.List;
import java.util.Map;
import java.util.Queue;
import java.util.stream.Collectors;

@Service
@Slf4j
public class SetmealServiceImpl extends ServiceImpl<SetmealMapper, Setmeal> implements SetmealService {

    @Autowired
    private DishService dishService;

    @Autowired
    private SetmealDishService setmealDishService;

    /**
     * 新增套餐, 同时保存套餐和菜品的关联关系
     * @param setmealDto
     */
    @Transactional
    public void saveWithDish(SetmealDto setmealDto) {
        //保存套餐的基本信息, 操作setmeal, 执行insert操作
        this.save(setmealDto);

        List<SetmealDish> setmealDishes = setmealDto.getSetmealDishes();
        setmealDishes = setmealDishes.stream().map((item)->{
            item.setSetmealId(setmealDto.getId());
            return item;
        }).collect(Collectors.toList());

        //保存套餐和菜品的关联信息, 操作setmeal_dish, 执行insert操作
        setmealDishService.saveBatch(setmealDishes);
    }

    /**
     * 删除套餐, 同时需要删除套餐和菜品的关联数据
     * @param ids
     */
    @Transactional
    public void removeWithDish(List<Long> ids) {
        //select count(*) from setmeal where id in (1, 2, 3) and status = 1
        //查询套餐的状态, 确定是否可以删除
        LambdaQueryWrapper<Setmeal> queryWrapper = new LambdaQueryWrapper<>();
        queryWrapper.in(Setmeal::getId, ids);
        queryWrapper.eq(Setmeal::getStatus, 1);

        int count = this.count(queryWrapper);
        if (count > 0){
            //如果不能删除, 抛出一个业务异常
            throw new CustomException("套餐正在售卖中, 不能删除");
        }

        //如果可以删除, 先删除套餐表中的数据----setmeal
        this.removeByIds(ids);

        //delete from setmeal_dish where setmeal_id in (1, 2, 3)
        LambdaQueryWrapper<SetmealDish> lambdaQueryWrapper = new LambdaQueryWrapper<>();
        lambdaQueryWrapper.in(SetmealDish::getSetmealId, ids);
        //删除关系表中的数据----setmeal_dish
        setmealDishService.remove(lambdaQueryWrapper);
    }

    /**
     * 起售套餐条件判断
     * @param ids
     */
    public boolean saleCondition(List<Long> ids) {
        //分页构造器对象
        Page<SetmealDish> pageInfo = new Page<>();

        //条件构造器
        LambdaQueryWrapper<SetmealDish> queryWrapper = new LambdaQueryWrapper<>();
        queryWrapper.in(SetmealDish::getSetmealId, ids);

        //查询
        setmealDishService.page(pageInfo, queryWrapper);

        //得到套餐菜品关系对象集合
        List<SetmealDish> records = pageInfo.getRecords();

        List<Long> dishIds = records.stream().map((item)->{
            return item.getDishId();
        }).collect(Collectors.toList());

        LambdaQueryWrapper<Dish> lambdaQueryWrapper = new LambdaQueryWrapper<>();
        lambdaQueryWrapper.in(Dish::getId, dishIds);
        lambdaQueryWrapper.eq(Dish::getStatus, 0);
        int count = dishService.count(lambdaQueryWrapper);

        return count == 0;
    }
}
